Karsakpai is situated in the central area of the Mai-Tubinskii anticlinorium and lies amongst Middle Proterozoic crystalline schists, amphibolites and granite gneisses. The complex is about 6x4 km and has a concentric ring structure. It is composed principally of alkaline melanocratic syenites, with rather less abundant leucocratic ones; liebenerite syenites and nepheline syenites are subordinate. The complex was generated by the intrusion of the following phases: (1) monzonite and syenite-diorite; (2) albite-hastingsite syenite; (3) feldspar-bearing urtite; (4) melanocratic alkaline syenite (lepidomelane-hastingsite, augite-hastingsite and lepidomelane); (5) nepheline syenite; (6) dykes including trachytic syenites, syenite porphyries and syenite pegmatites. Albitised and liebeneritized syenites occur throughout the complex.
NURLIBAYEV, A.N. and PANCHENKO, A.G. 1968. Alkaline and subalkaline rocks of Northern Kazakhstan and Kirgizia. Izd-vo Nauka Kazakskoi SSR, Alma-Ata. 100-7.